Construction is one of the oldest fields of activities, during which auxiliary constructions are normally used, which facilitate the main process of construction. Some time ago, the function of these auxiliary constructions was performed by wooden constructions, while nowadays, in case of especially high buildings, the function of auxiliary constructions is performed by the construction supports (so called formwork props). These formwork props have one important drawback: if they are at least a little bit coincidentally dented or locally deformed, they become inappropriate and normally are thrown away, because their restoration is not easy. Practically, there are no effective, light and mobile tools, designed for restoration of the formwork props of this type.
There is one known French patent No. FR2924143, published on May 29 of 2009. This patent describes formwork prop, which at the endings is strengthened with additional elements, having the same form as the mentioned formwork prop. These elements protect the formwork prop from impact and from external dents in those places, to which the mentioned additional elements are mounted. However, this is only preventive protection of the formwork props, which protects the formwork props only close to their endings, but does not ensure protection in the whole area of the formwork prop and does not solve the issue of the formwork prop repair/restoration, when the formwork prop is already damaged.
There is another known Chinese patent No. CN2168912, published on Jun. 15 of 1996. This patent describes a device designed for straightening construction supports (formwork props) that are made of steel. This device consists of a special table, onto which the formwork prop is laid, and an engine mechanism, which, when using rails arranged in line one after another, moves the mentioned support over the entire length of the device and, in this way, straightens the formwork prop. The structure itself is simple; however, it is fairly large. It requires separately intended and prepared space. Electric energy is also needed for operation/supply of this equipment. Another drawback is that this system can straighten the formwork props only from the outside and not from the inside.
Another known patent is Russian patent No. RU2372549, published on Nov. 10 of 2009. This patent describes a device, which is inlet into the pipe, able to check the cleanliness level, as well as, by using the compressed air or water under pressure, clean the inner area of the indicated part of the pipe wall. This device is practical, when sand, mud or other undesirable materials get into the formwork prop, however, this device is not suitable for straightening the formwork prop from the inside, because compressed air and water pressure is not enough for performing these works. Moreover, compressor, water or air supply system is required.
There is one more known German patent No. DE102007034140, published on Jun. 5 of 2008. This patent describes a cone-shaped device, with the rotating head, made of diamond or other hard material, which can rotate around its axis. This rotating head is inlet into a pipe or pipe-shaped structure and, in this way, it can clean the inner walls of the pipe-shaped structures from dirt and blockage. Furthermore, it can lengthen and restore minor dents, directed to the inside, of the pipe-shaped structures. However, this system uses electric energy, rotating parts requite special caution, and it is possible to remove only very small dents.
The closest patent according to the prior art is Latvian patent No. LV12774, published on Mar. 20 of 2002. This patent describes hydraulic structure designed for removing the holes or cracks of the formwork props. When using a hydraulic piston, this structure is inlet into the formwork prop and moved along the inner wall of the formwork prop. The mentioned structure has a sealing gasket, which, when the structure is moving from one ending to another, gets and distributes in all holes and cracks of the formwork prop. However, this structure does not foresee the inner local geometry correction of the formwork props, for example, caves, dents and etc.